<template>
  <ul>
    <li :style="{opacity}">欢迎学习Vue</li>
    <li>news001：<input type="text"></li>
    <li>news002：<input type="text"></li>
    <li>news003：<input type="text"></li>
  </ul>
</template>

<script>
export default {
  name: "News",
  data() {
    return {
      opacity: 1
    }
  },
  // beforeDestroy(){
  //   console.log('News组件即将被销毁了')
  //   clearInterval(this.timer)
  // },
  // mounted() {
  //   this.timer = setInterval(() => {
  //     this.opacity -= 0.01
  //     if(this.opacity <= 0) this.opacity = 1
  //   })
  // }


  //当这个组件被使用的时候执行的代码
  activated() {
    console.log('News组件被激活了')

    this.timer = setInterval(() => {
      console.log('@')
      this.opacity -= 0.01
      if (this.opacity <= 0) this.opacity = 1
    })
  },
  //当离开这个组件的时候执行的代码
  deactivated() {
    console.log('News组件失活了')
    clearInterval(this.timer)
  }
}
</script>

<style scoped>

</style>